Sikh and Muslim perspectives on kidney transplantation: phase 1 of the DiGiT project - a qualitative descriptive study.

OBJECTIVES: Kidney transplantation offers patients better quality of life and survival compared with dialysis. The risk of end stage renal disease is higher among ethnic minorities and they experience longer wait times on transplant lists. This inequality stems from a high need for kidney transplantation combined with a low rate of deceased donation among ethnic minority groups. This study aimed to explore the perspectives around living donor kidney transplantation of members of the Sikh and Muslim communities with an aim to develop a digital intervention to overcome any barriers. DESIGN: A qualitative descriptive study using in person focus groups. SETTING: University Teaching Hospital and Transplant Centre. PARTICIPANTS: Convenience sampling of participants from the transplant population. Three focus groups were held with 20 participants, all were of South Asian ethnicity belonging to the Sikh and Muslim communities. METHODS: Interviews were digitally audio-recorded and transcribed verbatim; transcripts were analysed thematically. RESULTS: Four themes were identified: (a) religious issues; (b) lack of knowledge within the community; (c) time; (d) cultural identification with transplantation. CONCLUSIONS: Not only is the information given and when it is delivered important, but also the person giving the information is crucial to enhance consideration of live donor kidney transplantation. Information should be in a first language where possible and overtly align to religious considerations. A more integrated approach to transplantation counselling should be adopted which includes healthcare professionals and credible members of the target cultural group. TRIAL REGISTRATION NUMBER: NCT04327167.

Do we practice what we preach? Dialysis modality choice among healthcare workers in the United Kingdom.

BACKGROUND: In the United Kingdom, over 80% of end-stage kidney disease patients receive in-center hemodialysis. We conducted a survey of UK renal healthcare workers on their preferred dialysis modality if they needed dialysis themselves. METHODS: An anonymized online survey was disseminated to all renal healthcare workers in the United Kingdom. We asked "Assume you are an otherwise well 40-year-old (and, separately, 75-year-old) person approaching end stage kidney disease, you have no living kidney donor options at present. There are no contraindications to any dialysis options. Which dialysis therapy would you choose?" We also asked about factors influencing their choice. RESULTS: 858 individuals with a median age of 44.3 years responded. 70.2% were female, 37.4% doctors, and 31.1% were senior nurses. There was a preference for peritoneal dialysis over in-center hemodialysis (50.47% v. 6.18%; p < 0.001 for 40-year-old and 49.18% v. 17.83%; p < 0.001 for 75-year-old assumption) and home hemodialysis (50.47% v. 39.28%; p < 0.001 for 40-year-old and 49.18% v. 18.41% for 75-year-old assumption). There was a preference for home hemodialysis over in-center hemodialysis for 40-year-old (39.28% v. 6.18%; p < 0.001) but not for 75-year-old. On logistic regression, senior doctors were more likely to opt for PD when compared to nurses. Nurses, allied healthcare professionals, and those of Asian/British Asian ethnicity were more likely to choose in-center hemodialysis. CONCLUSIONS: Most healthcare workers in renal medicine would choose home-based treatment for themselves although the majority of end-stage kidney disease patients receive in-center hemodialysis in the United Kingdom; the reasons for the discrepancy need to be explored.

Outcomes of Remote Patient Monitoring in Peritoneal Dialysis: A Meta-Analysis and Review of Practical Implications for COVID-19 Epidemics.

The present study seeks to determine clinical outcomes associated with remote patient monitoring of peritoneal dialysis (RPM-PD), with potential implications during COVID-19 outbreaks. We performed a systematic review in the PubMed, Embase, and Cochrane databases. We combined all study-specific estimates using the inverse-variant weighted averages of logarithmic relative risk (RR) in the random-effects models. Confidence interval (CI) including the value of 1 was used as evidence to produce a statistically significant estimate. Twenty-two studies were included in our meta-analysis. Quantitative analysis demonstrated that RPM-PD patients had lower rates of technique failure (log RR = -0.32; 95% CI, -0.59 to -0.04), lower hospitalization rates (standardized mean difference = -0.84; 95% CI, -1.24 to -0.45), and lower mortality rates (log RR = -0.26; 95% CI, -0.44 to -0.08) compared with traditional PD monitoring. RPM-PD has better outcomes in multiple spheres of outcomes when compared with conventional monitoring and likely increases system resilience during disruptions of healthcare operations.

Risk factors associated with COVID-19 severity among patients on maintenance haemodialysis: a retrospective multicentre cross-sectional study in the UK.

OBJECTIVES: To assess the applicability of risk factors for severe COVID-19 defined in the general population for patients on haemodialysis. SETTING: A retrospective cross-sectional study performed across thirty four haemodialysis units in midlands of the UK. PARTICIPANTS: All 274 patients on maintenance haemodialysis who tested positive for SARS-CoV-2 on PCR testing between March and August 2020, in participating haemodialysis centres. EXPOSURE: The utility of obesity, diabetes status, ethnicity, Charlson Comorbidity Index (CCI) and socioeconomic deprivation scores were investigated as risk factors for severe COVID-19. MAIN OUTCOMES AND MEASURES: Severe COVID-19, defined as requiring supplemental oxygen or respiratory support, or a C reactive protein of ≥75 mg/dL (RECOVERY trial definitions), and its association with obesity, diabetes status, ethnicity, CCI, and socioeconomic deprivation. RESULTS: 63.5% (174/274 patients) developed severe disease. Socioeconomic deprivation associated with severity, being most pronounced between the most and least deprived quartiles (OR 2.81, 95% CI 1.22 to 6.47, p=0.015), after adjusting for age, sex and ethnicity. There was no association between obesity, diabetes status, ethnicity or CCI with COVID-19 severity. We found no evidence of temporal evolution of cases (p=0.209) or clustering that would impact our findings. CONCLUSION: The incidence of severe COVID-19 is high among patients on haemodialysis; this cohort should be considered high risk. There was strong evidence of an association between socioeconomic deprivation and COVID-19 severity. Other risk factors that apply to the general population may not apply to this cohort.

Regional variations in nephrology trainee confidence with clinical skills may relate to the availability of local training opportunities in the UK: results from a national survey.

BACKGROUND: The United Kingdom offers a standardised training program for nephrology fellows. However, local training opportunities vary resulting in mismatches between trainee interests and accessible opportunities. This may impact trainee confidence, satisfaction, and future service provision. METHODS: A survey assessing confidence with key procedures and sub-specialities was disseminated. Associations with region of training were probed using Chi square tests, with significance set at p < 0.0008 following a Bonferroni correction. Results were compared to trainee views on available opportunities for development. RESULTS: 139 responses were received (32% response rate, demographics representative of the UK nephrology trainee cohort). Procedural independence varied from 98% for temporary femoral vascular catheters to 5% for peritoneal dialysis catheters (PDIs). Independence with inserting tunnelled vascular catheters varied with region (p < 0.0001). Trainees expressed a desire for formal training in kidney ultrasound scanning and PDIs, corresponding with procedures they had least opportunity to become independent with. Trainees felt least confident managing kidney disease in pregnancy. Suggestions for improving training included protected time for garnering sub-speciality knowledge, developing procedural skills and for experiencing practice in other nephrology units. CONCLUSIONS: A mismatch between trainee interests and professional development opportunities exists, which may threaten trainee autonomy and impact patient care particularly with regards to peritoneal dialysis. Provisions to facilitate trainee directed development need to be made while balancing the rigors of service provision. Such measures could prove critical to promoting trainee well-being and preventing attrition within the nephrology workforce.

Effects of fasting on solid organ transplant recipients during Ramadan - a practical guide for healthcare professionals.

Fasting in the month of Ramadan is an obligatory act for healthy adult Muslims. It requires abstinence from food and drink from dawn to sunset. Although there are exemptions from fasting, many patients are keen to fulfil what they see as a religious obligation, even if this may be against medical advice in some cases. Solid organ transplant (SOT) recipients often ask healthcare professionals for advice on fasting. Studies on the effect of fasting in transplant patients have all been done in the Middle East and North Africa where the average fasting duration is between 12 and 14 hours. In comparison, in temperate regions in the summer, fasting duration can be as long as 20 hours. Fasting when patients have to take immunosuppression 12 hours apart with little time variation poses unique challenges. In this review, current literature is reviewed, and a decision-making tool has been developed to assist clinicians in discussing the risks of fasting in transplant recipients, with consideration also given to circumstances such as the COVID-19 pandemic.Our review highlights that SOT recipients wishing to fast should undergo a thorough risk assessment, ideally 3 months before Ramadan. They may require medication changes and a plan for regular monitoring of graft function and electrolytes in order to fast safely. Recommendations have been based on risk tiers (very high risk, high risk and low/moderate risk) established by the International Diabetes Federation and the Diabetes and Ramadan International Alliance. Patients in the 'very high risk' and 'high risk' categories should be encouraged to explore alternative options to fasting such as winter fasting or Fidyah. Those in the 'low/moderate' category may be able to cautiously fast with guidance from their clinician. Prior to the commencement of Ramadan, all patients must receive up-to-date education on sick-day rules, instructions on when to terminate their fast or abstain from fasting.

Effects of fasting on patients with chronic kidney disease during Ramadan and practical guidance for healthcare professionals.

There are an estimated 1.8 billion Muslims worldwide, with the majority of them choosing to fast during the month of Ramadan. Fasting, which requires abstinence from food and drink from dawn to sunset can be up to 20 h per day during the summer months in temperate regions. Fasting can be especially challenging in patients on haemodialysis and peritoneal dialysis. Moreover, there is concern that those with chronic kidney disease (CKD) can experience electrolyte imbalance and worsening of renal function. In this article, current literature is reviewed and a decision-making management tool has been developed to assist clinicians in discussing the risks of fasting in patients with CKD, with consideration also given to circumstances such as the coronavirus disease 2019 pandemic. Our review highlights that patients with CKD wishing to fast should undergo a thorough risk assessment ideally within a month before Ramadan, as they may require medication changes and a plan for regular monitoring of renal function and electrolytes in order to fast safely. Recommendations have been based on risk tiers (very high risk, high risk and low-moderate risk) established by the International Diabetes Federation and the Diabetes and Ramadan International Alliance. Patients in the very high risk and high risk categories should be encouraged to explore alternative options to fasting, while those in the low-moderate category may be able to fast safely with guidance from their clinician. Prior to the commencement of Ramadan, all patients must receive up-to-date education on sick-day rules and instructions on when to terminate their fast or abstain from fasting.

Behaviour of non-donor specific antibodies during rapid re-synthesis of donor specific HLA antibodies after antibody incompatible renal transplantation.

BACKGROUND: HLA directed antibodies play an important role in acute and chronic allograft rejection. During viral infection of a patient with HLA antibodies, the HLA antibody levels may rise even though there is no new immunization with antigen. However it is not known whether the converse occurs, and whether changes on non-donor specific antibodies are associated with any outcomes following HLA antibody incompatible renal transplantation. METHODS: 55 patients, 31 women and 24 men, who underwent HLAi renal transplant in our center from September 2005 to September 2010 were included in the studies. We analysed the data using two different approaches, based on; i) DSA levels and ii) rejection episode post transplant. HLA antibody levels were measured during the early post transplant period and corresponding CMV, VZV and Anti-HBs IgG antibody levels and blood group IgG, IgM and IgA antibodies were quantified. RESULTS: Despite a significant DSA antibody rise no significant non-donor specific HLA antibody, viral or blood group antibody rise was found. In rejection episode analyses, multiple logistic regression modelling showed that change in the DSA was significantly associated with rejection (p = 0.002), even when adjusted for other antibody levels. No other antibody levels were predictive of rejection. Increase in DSA from pre treatment to a post transplant peak of 1000 was equivalent to an increased chance of rejection with an odds ratio of 1.47 (1.08, 2.00). CONCLUSION: In spite of increases or decreases in the DSA levels, there were no changes in the viral or the blood group antibodies in these patients. Thus the DSA rise is specific in contrast to the viral, blood group or third party antibodies post transplantation. Increases in the DSA post transplant in comparison to pre-treatment are strongly associated with occurrence of rejection.

Elevated pretransplantation soluble BAFF is associated with an increased risk of acute antibody-mediated rejection.

BACKGROUND: B cells play an important role in renal allograft pathology, particularly in acute and chronic antibody-mediated rejection (AMR). B-cell activating factor belonging to the tumor necrosis factor family (BAFF; also known as BLyS) is a cytokine that enhances B-cell survival and proliferation. METHODS: We analyzed serum BAFF levels in 32 patients undergoing antibody-incompatible (Ai) renal transplantation and 319 antibody-compatible transplant recipients and sought to determine whether there was a correlation with acute rejection and with transplant function and survival. RESULTS: We demonstrate that, in patients undergoing Ai transplantation, elevated serum BAFF levels at baseline (before both antibody removal/desensitization and transplantation) are associated with an increased risk of subsequent AMR. In antibody-compatible transplant recipients at lower risk of AMR, no statistically significant association was observed between pretransplantation serum BAFF and AMR. CONCLUSIONS: These data raise the possibility that, in high immunologic risk patients undergoing Ai transplantation, the presence of elevated pretransplantation serum BAFF might identify those at increased risk of AMR. BAFF neutralization may be an interesting therapeutic strategy to explore in these patients, particularly because such agents are available and have already been used in the treatment of autoimmunity.

Human leukocyte antigen-specific antibodies and gamma-interferon stimulate human microvascular and glomerular endothelial cells to produce complement factor C4.

BACKGROUND: The role of the complement system in antibody-mediated rejection has been investigated in relation to circulating complement interacting with renal microvascular endothelium, resulting in the formation of peritubular capillary C4d. However, the possible importance of local complement synthesis is less clear. The aim of this study was to determine whether human vascular endothelium could produce C4 in response to stimulation in vitro. METHODS: Human microvascular endothelial cells and glomerular endothelial cells were stimulated with endotoxins, cytokines, and human leukocyte antigen-specific antibodies. Synthesis of complement was investigated using western blotting and indirect immunofluorescence. De novo C4 synthesis was confirmed by using C4 small interfering RNA. RESULTS: Glomerular and microvascular endothelium, both produce C3 and C4 complement protein. Complement synthesis was stimulant-specific-C3 was produced mainly after stimulation with lipopolysaccharide whereas C4 synthesis occurred on treatment with gamma interferon. Culture with human leukocyte antigen-specific antibodies resulted in a significant increase of C4 protein synthesis by both cell lines. CONCLUSIONS: We have shown for the first time that human microvascular endothelium can be stimulated to synthesize C4 in vitro. The implications of this for clinical transplantation, especially in the context of antibody-mediated rejection, its histological interpretation and as a potential target for therapy would have to be determined by further studies.

Cryofiltration in the treatment of cryoglobulinemia and HLA antibody-incompatible transplantation.

Cryofiltration is a technique in which plasma is separated from blood and chilled, leading to the formation of "cryogel", a composite of heparin, fibronectin, fibrinogen, immunoglobulins, and other proteins. This is retained by further filtration and plasma is returned to the patient. There may be a role for cryofiltration in the treatment of cryoglobulinemia or where the application of other forms of plasmapheresis or immunoadsorption is limited. Five patients received six courses of cryofiltration. Two patients had cryoglobulinemia and three were treated before HLA antibody-incompatible renal transplantation. The treatment was associated with few adverse effects, and it was possible to treat up to 120 mL/kg plasma per session. There was a good clinical response in four patients. One patient was switched back to double filtration plasmapheresis (DFPP) because cryofiltration seemed to remove HLA antibodies less effectively, but the other two transplants have excellent function. In the cryoglobulinemia patients there was excellent clearance of cryoglobulins during each treatment (mean decrease of 78.2 (SD 14.1)% per treatment). Compared with DFPP, fewer immunoglobulins were removed and the mean percentage reductions in immunoglobulin G per treatment were 36.0 (4.0)% for cryoglobulinemia and 59.2 (2.5)% for DFPP (P < 0.01), with respective mean plasma volumes of 64.2 (10.3) and 71.1 (6.8) mL/kg treated. Cryofiltration offers a treatment choice in patients with cryoglobulinemia and in those who may not be able to tolerate high-volume DFPP. The technique used in the patients described here was less effective than DFPP; however, use of an alternative fractionator and treatment of higher plasma volumes may enhance the efficiency of cryofiltration.

Human leukocyte antigen antibody-incompatible renal transplantation: excellent medium-term outcomes with negative cytotoxic crossmatch.

BACKGROUND: Human leukocyte antigen (HLA) antibody-incompatible renal transplantation has been increasingly performed since 2000 but with few data on the medium-term outcomes. METHODS: Between 2003 and 2011, 84 patients received renal transplants with a pretreatment donor-specific antibody (DSA) level of more than 500 in a microbead assay. Seventeen patients had positive complement-dependent cytotoxic (CDC) crossmatch (XM), 44 had negative CDC XM and positive flow cytometric XM, and 23 had DSA detectable by microbead only. We also reviewed 28 patients with HLA antibodies but no DSA at transplant. DSAs were removed with plasmapheresis pretransplant, and patients did not routinely receive antithymocyte globulin posttransplant. RESULTS: Mean follow-up posttransplantation was 39.6 (range 2-91) months. Patient survival after the first year was 93.8%. Death-censored graft survival at 1, 3, and 5 years was 97.5%, 94.2%, and 80.4%, respectively, in all DSA+ve patients, worse at 5 years in the CDC+ve than in the CDC-ve/DSA+ve group at 45.6% and 88.6%, respectively (P<0.03). Five-year graft survival in the DSA-ve group was 82.1%. Rejection occurred in 53.1% of DSA+ve patients in the first year compared with 22% in the DSA-ve patients (P<0.003). CONCLUSIONS: HLA antibody-incompatible renal transplantation had a high success rate if the CDC XM was negative. Further work is required to predict which CDC+ve XM grafts will be successful and to treat slowly progressive graft damage because of DSA in the first few years after transplantation.

Double filtration plasmapheresis in antibody-incompatible kidney transplantation.

Double filtration plasmapheresis (DFPP) was used in preference to plasma exchange in our program of antibody-incompatible transplantation, to treat higher volumes of plasma. Forty-two patients had 259 sessions of DFPP, 201 pre-transplant and 58 post-transplant. At the first treatment session, the mean plasma volume treated was 3.81 L (range 3-6 L), 55.5 mL/kg (range 36.2-83.6 mL/kg). Serum IgG fell by mean 59.4% (SD 10.2%), and IgM by 69.3% (SD 16.1%). Nine patients did not require increases in plasma volumes treated, and six did not tolerate higher plasma volumes. In the remaining patients, the mean maximum plasma volume treated pre-transplant was 6.67 L (range 4-15 L), 96.1 mL/kg (range 60.2-208.9 mL/kg). The complement dependent cytotoxic crossmatch was positive in 14 cases pre-treatment, and remained positive in six (42.8%) cases. The flow cytometric crossmatch was positive in 29 cases pre-treatment, and in 21 (72.4%) after DFPP. Post-transplant, DFPP was ineffective at reducing donor specific antibody levels during periods of rapid donor specific antibody synthesis. Post-transplant, the one year graft survival rate was 94%, although there was a high rate of early rejection. In summary, DFPP enabled the treatment of plasma volumes that were almost double those that would have been feasible with plasma exchange. Despite this, most patients were transplanted with a positive crossmatch, and DFPP post-transplant was unable to control rising antibody levels.

Soluble CD30 and Cd27 levels in patients undergoing HLA antibody-incompatible renal transplantation.

HLA antibody-incompatible transplantation has a higher risk of rejection when compared to standard renal transplantation. Soluble CD30 (sCD30) has been shown in many, but not all, studies to be a biomarker for risk of rejection in standard renal transplant recipients. We sought to define the value of sCD30 and soluble CD27 (sCD27) in patients receiving HLA antibody-incompatible transplants. Serum taken at different time points from 32 HLA antibody-incompatible transplant recipients was retrospectively assessed for sCD30 and sCD27 levels by enzyme-linked immunosorbent assay (ELISA). This was compared to episodes of acute rejection, post-transplant donor-specific antibody (DSA) levels and 12 month serum creatinine levels. No association was found between sCD27 and sCD30 levels and risk of acute rejection or DSA levels. Higher sCD30 levels at 4-6 weeks post-transplantation were associated with a higher serum creatinine at 12 months. Conclusion patients undergoing HLA antibody-incompatible transplantation are at a high risk of rejection but neither sCD30 (unlike in standard transplantation) nor sCD27 was found to be a risk factor. High sCD30 levels measured at 4-6 weeks post-transplantation was associated with poorer graft function at one year.

The histological development of acute antibody-mediated rejection in HLA antibody-incompatible renal transplantation.

BACKGROUND: The aim of this study was to examine the development of acute antibody-mediated rejection in HLA antibody-incompatible renal transplantation in relation to the Banff 07 histological classification. METHODS: Renal biopsies were scored using the Banff 07 diagnostic criteria, and paraffin-embedded sections were stained with the pan-leucocyte marker CD45. RESULTS: Thirty-six patients had 72 renal biopsies. In biopsies performed 30 min after graft reperfusion, the mean number of CD45+ cells per glomerulus was higher than in control grafts (P < 0.04) and was associated with the donor-specific antibody (DSA) level at transplantation measured by microbeads (P < 0.01), and eight out of nine patients with greater than five CD45+ cells per glomerulus had early post-transplant rejection or oliguria, compared to 11 out of 20 with less than five cells per glomerulus (P < 0.01). In the first 10 days post-transplant, although peritubular capillary (PTC) leucocyte margination grade 3 and C4d deposition were specific for rejection, their sensitivities were low. PTC C4d staining was only seen in two out of 11 biopsies taken in the first 5 days after transplant, even in the presence of rejection, but was present in the majority of later biopsies with rejection. In biopsies stained for CD3, CD68 and CD20, it was notable that CD20+ cells were not seen during acute rejection, the infiltrates comprising CD3+ and CD68+ leucocytes. CONCLUSIONS: Glomerular margination of leucocytes occurred early after transplantation and was associated with DSA level and early graft dysfunction. The Banff 07 PTC margination scoring system was easy to apply, especially when CD45 staining was used, and PTC margination grade 3 was always associated with clinical rejection.

Rises and falls in donor-specific and third-party HLA antibody levels after antibody incompatible transplantation.

BACKGROUND: After human leukocyte antigen (HLA) antibody-incompatible transplantation, donor specific and third party HLA antibodies may be found, and their levels fall in a donor-specific manner during the first month. However, these changes have not been previously described in detail. METHODS: Donor-specific HLA antibody (DSA) and third-party HLA antibody (TPA) levels were measured using the microbead method in 44 presensitized patients who had renal transplantation. RESULTS: DSA+TPA fell in the first 4 days after transplantation, and greater falls in DSA indicated absorption by the graft. This occurred for class I (57.8% fall compared with 20.2% for TPA, P<0.0005), HLA DR (63.0% vs. 24.3%, P<0.0004), and for HLA DP/DQ/DRB3-4 (34% vs. 17.5%, P=0.014). Peak DSA levels occurred at a mean of 13 days posttransplant, and they were higher than pretreatment in 25 (57%) patients and lower in 19 (43%) patients (P=ns). The risk of rejection was associated with peak DSA levels; 15 of 25 (60%) patients with DSA at median fluorescence intensity (MFI) more than 7000U experienced rejection, compared with 4 of 7 (57%) patients with peak DSA MFI 2000 to 7000U, and 2 of 12 (17%) patients with peak DSA MFI less than 2000U (P<0.02). DSA levels subsequently fell in a donor specific manner compared to TPA. CONCLUSION: DSA levels may change markedly in the first month after antibody incompatible transplantation, and the risk of rejection was associated with higher pretreatment and peak levels.

Application of flow cytometry to monitor antibody levels in ABO incompatible kidney transplantation.

Current methods of measuring ABO antibody levels based on the hemagglutination (HA) titers have the disadvantages of relatively poor reproducibility and do not offer fine discrimination of antibody concentration. We therefore developed a simple and rapid method of measuring ABO antibody levels using flow cytometry (FC). For validation, we analyzed plasma samples from 79 blood donors. Both IgM and IgG were detected and measured with IgG essentially restricted blood group O donors. Forty-two successive samples were collected from a patient with blood group O undergoing antibody removal and subsequent transplantation from a group A2 donor and tested by both HA and FC. Changes in IgG measured by FC (relative median fluorescence) correlated well with HA titers and importantly rejection episodes were preempted by a rising relative median fluorescence. The method allowed quantitative discrimination in the range of antibody levels relevant to ABO incompatible transplantation and has the advantages over HA of objective measurement and reproducibility.

New choices for patients needing kidney transplantation across antibody barriers.

Antibodies in the blood of a kidney transplant recipient can provide a barrier to transplantation, which is additional to the usual possibility of cellular rejection. The antibodies most frequently encountered are ABO (blood group) and human leucocyte antigen (HLA) (tissue-type) antibodies. About 250 living donor transplants each year in the United Kingdom have been stopped because of an antibody barrier. It is now possible to offer a choice of treatment modalities to these people, including exchange transplantation and antibody-incompatible transplantation. It is likely that both schemes will complement each other and both are available in the United Kingdom.

Blood levels of donor-specific human leukocyte antigen antibodies after renal transplantation: resolution of rejection in the presence of circulating donor-specific antibody.

BACKGROUND: Accommodation to antibody is an important mechanism in successful ABO-incompatible transplantation, but its importance in human leukocyte antigen (HLA) antibody-incompatible transplantation is less clear, as sensitive techniques facilitating daily measurement of donor-specific HLA antibodies (DSAs) have only recently been developed. METHODS: We report 24 patients who had HLA antibody-incompatible kidney transplantation (21 living donors, 3 deceased), 21 of whom had pretransplant plasmapheresis. Eight had positive complement-dependent cytotoxic (CDC) crossmatch (XM) pretransplant plasmapheresis, nine had positive flow cytometric (FC) XM, and seven had DSA detectable by microbead analysis only. After transplant, DSA levels were monitored closely with microbead assays. RESULTS: Rejection occurred in five of eight (62.5%) CDC-positive cases, in three of nine (33%) FC-positive cases, and in two of seven (29%) of microbead-only cases at a median of 6.5 days after transplantation. Resolution occurred at a median of 15 days after transplantation, in 8 of 10 cases when the microbead level of DSA had median fluorescence intensity (MFI) >2000 U, in 6 of 10 when the microbead MFI >4000 U. In 8 of 10 cases, the microbead MFI at the time of resolution was greater than at the onset. DSA did not always cause clinical rejection. In five cases with a posttransplant DSA peaking at MFI >2000 U on microbead assay, rejection did not occur. CONCLUSION: These data suggest that the dominant method of successful transplantation was function of the transplant in the presence of circulating DSA, and they also define the period during which this occurred.